Water supply apparatus

ABSTRACT

A water supply apparatus includes an apparatus body disposed in a flow passage for sucking water to an indoor facility and a power generation unit installed in the apparatus body. Further, the power generation unit further comprises a rotating shaft extended in a direction perpendicular to the water channel direction of the flow passage, and impeller installed on the rotating shaft and rotated by a water flow, a magnet rotated interlockingly with the impeller, and a coil arranged oppositely to the magnet, wherein the impeller forms blades in the radial outer direction and forms clearances allowing water to pass to the inside of the blades. Since the clearances are formed between the blades and the rotating shaft such a trouble that water flowing into the base ends of the blades obstructs the rotation of the impeller can be eliminated to increase a power generation amount by the power generation unit. In addition, since there is no need to expand the flow passage on the outside of the impeller to reduce the rotational resistance of the impeller, the size of the water supply apparatus can be reduced.

TECHNICAL FIELD

The present invention relates to a water supply apparatus which installsa power generating unit in a midst of a flow passage which supplieswater to an indoor facility. Here, the indoor facility indicates awater-related facility such as a sink, a wash basin, a toilet bowl, awashing machine or the like which are used in public facilities such asoffices and stations and residences and is also a facility which usesservice water, intermediate water, sewage, well water, rains and thelike.

BACKGROUND ART

Conventionally, a water supply apparatus which installs a powergenerating unit in a midst of a flow passage for supplying water to anindoor facility has been popularly used. In such a water supplyapparatus, the power generating unit generates an electric power bymaking use of a water flow in the inside of the flow passage and variouselectronic equipment such as sensors and switches which are mountedinside or outside the water supply apparatus are driven using thegenerated electricity.

For example, in an automatic water supply apparatus disclosed inJapanese Patent Laid-open Publication Sho59(1984)-217074, a flow passageis formed in the inside of an apparatus body, a rotary shaft whoserotating axis extends in the direction orthogonal to the direction of awater flow is rotatably provided in a midst of the flow passage, andblades are formed on an outer periphery of the rotary shaft in a statethat the blades extend in the radial direction.

Further, the rotary shaft is rotated together with the blades due to thewater flow and electric power is generated due to the rotation of therotary shaft.

Further, in a sterilizer of toilet boll flushing water disclosed inJapanese Patent Laid-open Publication 2000-27262, a flow passage isformed in the inside of an apparatus body, a rotary shaft whose rotatingaxis extends in the direction orthogonal to the direction of a waterflow is rotatably provided in a midst of the flow passage, and bladesare formed on an outer periphery of the rotary shaft in a state that theblades extend in the radial direction, and a power generator isconnected to the rotary shaft.

Further, the rotary shaft is rotated together with the blades due to thewater flow and electric power is generated due to the rotation of therotary shaft.

However, in the conventional apparatus, the rotary shaft whose rotatingaxis extends in the direction orthogonal to the direction of the waterflow is rotatably provided in the midst of the flow passage, and theblades are formed on the outer periphery of the rotary shaft in a statethat the blades extend in the radial direction. That is, in theconventional apparatus, no clearances are formed between the rotaryshaft and the blades.

Accordingly, water which impinges on distal end portions of the bladesflows not only toward the outside than the distal ends of the blades butalso toward proximal end portions of the blades. Here, water which flowstoward the proximal end portions of the blades exhibits a trivial actionto rotate the blades and rather exhibits an action which functions asthe resistance against the rotation of the blades. That is, water whichflows toward the proximal end portions of the blades impedes therotation of the blades thus giving rise to a loss of amount of powergenerated by a power generator.

Further, the conventional apparatus adopts the structure in which therotating shaft is mounted on the apparatus body and does not adopt thestructure which allows the detachable mounting of the power generatingunit on the apparatus body and hence, an operation to assemble a powergenerating mechanism such as the rotary shaft and the blades to theapparatus body becomes cumbersome and, at the same time, the maintenanceoperation of the power generating mechanism also becomes cumbersome.

DISCLOSURE OF THE INVENTION

In view of the above-mentioned circumstances, according to the presentinvention, in a water supply apparatus in which an apparatus body isdisposed in a midst portion of a flow passage for supplying water to anindoor facility and a power generating unit is installed in theapparatus body, the power generating unit includes a rotating shaftextended in the direction orthogonal to the water flow direction of theflow passage, an impeller mounted on the rotating shaft and rotated by awater flow, a holder having a cylindrical portion with an arcuate crosssection along the impeller and having a shaft support portion whichsupports a proximal end portion of the rotary shaft on a distal end ofthe cylindrical portion, a magnet rotated interlockingly with theimpeller, and a coil arranged to face the magnet in the opposed manner,wherein the holder in the power generating unit is mounted on aperipheral surface of an opening portion formed in the apparatus body ina state that shaft support portion is inserted into the inside of theflow passage from the opening portion. and the impeller forms blades inthe outward radial direction and forms clearances allowing water to passthe inside of the blades.

Further, according to the present invention, the holder in the powergenerating unit is supported in a state that the distal end portion isfitted in an inner surface of the apparatus body which faces the openingportion of the apparatus body in an opposed manner.

Further, according to the present invention, in the above-mentionedpower generating unit, the magnet is disposed inside the flow passageand the coil is disposed outside the flow passage in a hermeticallypartitioned manner from the flow passage.

Further, according to the present invention, the above-mentioned powergenerating unit includes intrusion suppression means which suppressesthe intrusion of foreign substances between the blades and the magnet.

Further, according to the present invention, the above-mentionedintrusion suppression means is constituted by forming spear-headedthread-like grooves capable of generating a water flow which pushes backthe foreign substance to the blade side due to the rotation of theimpeller on an outer periphery of the impeller.

Further, according to the present invention, the power generating unitarranges the above-mentioned rotating shaft on a center axis of the flowpassage.

Further, according to the present invention, clearances are formedbetween outer peripheries of the blades and an inner wall of theabove-mentioned flow passage in a state that the clearances are arrangedasymmetrical with respect to an axis of the rotating shaft.

Further, according to the present invention, a guide member which guideswater toward the above-mentioned impeller is formed above thecylindrical portion.

Further, according to the present invention, a second guide member whichguides water toward the above-mentioned impeller is arranged at aposition where the second guide member faces the guide member in anopposed manner with the rotary shaft sandwiched therebetween.

BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 is a perspective view showing a connection state of a toilet bowlflushing apparatus which constitutes a water supply apparatus of thepresent invention;

FIG. 2 is an exploded perspective view showing the toilet bowl flushingapparatus;

FIG. 3 is a schematic view showing the toilet bowl flushing apparatus;

FIG. 4 is a front cross-sectional view showing the toilet bowl flushingapparatus;

FIG. 5 is a side cross-sectional view showing the toilet bowl flushingapparatus;

FIG. 6 is an exploded perspective view showing an apparatus body and apower generating unit;

FIG. 7 is an exploded perspective view showing the power generatingunit;

FIG. 8 is a graph showing the change of an output peak value of animpeller;

FIG. 9 is a plan view showing the connection state of the toilet bowlflushing apparatus;

FIG. 10 is a front cross-sectional view showing another embodiment ofthe toilet bowl flushing apparatus;

FIG. 11 is a perspective view showing another connection mode of thetoilet bowl flushing apparatus;

FIG. 12 is a front cross-sectional view showing a power generating unitfor an indoor facility which constitutes a water supply apparatus of thepresent invention;

FIG. 13 is a side cross-sectional view showing the power generating unitfor an indoor facility;

FIG. 14 is a schematic view showing another power generating unit for anindoor facility;

FIG. 15 is a graph showing the output characteristics of an impeller;

FIG. 16 is a cross-sectional view showing an impeller; and

FIG. 17 is a cross-sectional view showing another power generating unitfor an indoor facility.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the specific structure of the water supply apparatusaccording to the present invention is explained in conjunction withattached drawings.

(Toilet Bowl Flushing Apparatus)

FIG. 1 shows a toilet bowl flushing apparatus 1 which constitutes awater supply apparatus according to the present invention.

The toilet bowl flushing apparatus 1 is, as shown in FIG. 1, interposedbetween a water supply pipe 2 and a toilet bowl 3 and is served forsupplying water supplied from a water supply pipe 2 to the toilet bowl3. In the drawing, numeral 4 indicates a water stop valve. Here, thetoilet bowl 3 may be a waste bowl shown in FIG. 1 or a urine bowl shownin FIG. 11.

In the toilet bowl flushing apparatus 1, as shown in FIG. 2, a apparatusbody 6 is disposed in the inside of a casing 5.

As shown in FIG. 2, FIG. 4 and FIG. 5, the casing 5 has the splitstructure and is constituted of an upper cover 7 which covers an upperportion of the apparatus body 6, a front cover 8 which covers a lowerportion of a front side of the apparatus body 6, and a rear cover 9which covers a lower portion of a rear side of the apparatus body 6.

In the apparatus body 6, as shown in FIG. 2 to FIG. 6, while acylindrical water inlet 10 which is communicably connected with thewater supply pipe 2 is formed on an upper right side portion thereof, acylindrical water outlet 11 which is communicably connected with thetoilet bowl 3 is formed on a lower portion thereof.

Further, in the apparatus body 6, an open/close valve 12 is disposed ona downstream side of the water inlet 10 and, at the same time, a backpressure chamber 13 is formed in an upper portion of the open/closevalve 12. Further, a secondary-side water passage 14 is formed below theopen/close valve 12.

The water inlet 10 is communicably connected with the back pressurechamber 13 by way of a communication passage 15 which is formed in theinside of the open/close valve 12. The back pressure chamber 13 iscommunicably connected with the secondary-side water passage 14 by wayof first and second bypass flow passages 16, 17. An electromagneticvalve 18 is disposed in a midst portion of the first bypass flow passage16 and a manually operable valve 19 is disposed in a midst portion ofthe second bypass flow passage 17.

The electromagnetic valve 18 is connected with a control unit 20 whichis mounted on an upper portion of an inside of the casing 5.

To the control unit 20, besides the electromagnetic valve 18, a battery21, a human body detection sensor 22 and a power generating unit 23described later are connected. Further, in the control unit 20, chargingmeans into which electric energy generated by a power generating unit 23is charged is incorporated, and the electric energy is supplied torespective portions of the toilet bowl flushing apparatus 1 from thecharging means. On the other hand, when the generation of power is notperformed by the power generating unit 23 at the time of starting thetoilet bowl flushing apparatus 1 and for a long period, the electricenergy is supplied to the above-mentioned charging means from thebattery 21.

The apparatus body 6 has the above-mentioned constitution and supplieswater for flushing to the toilet bowl 3 as explained hereinafter.

First of all, in a state that the electromagnetic valve 18 and themanually operable valve 19 are closed, water which is supplied from thewater supply pipe 2 flows in the back pressure chamber 13 from the waterinlet 10 by way of the communication passage 15 and hence, the pressureinside the back pressure chamber 13 becomes higher than the pressureinside the secondary-side water passage 14 due to the water pressurewhereby the open/close valve 12 is closed.

Further, when the electromagnetic valve 18 is released upon receiving acontrol signal from the control unit 20, water flows in thesecondary-side water passage 14 from the back pressure chamber 13 by wayof the first bypass flow passage 16 and hence, the pressure differencebetween the secondary-side water passage 14 and the back pressurechamber 13 is instantly reduced. Along with the reduction of pressuredifference, the open/close valve 12 is moved to the upper back pressurechamber 13 side and hence, the water inlet 10 and the secondary-sidewater passage 14 are communicated with each other whereby a water flowsin the secondary-side water passage 14 from the water inlet 10 due tothe water pressure and, further, water is supplied to the toilet bowl 3from the water outlet 11.

Here, also when the manually operable valve 19 is released by the manualoperation, in the same manner, water flows in the secondary-side waterpassage 14 from the back pressure chamber 13 by way of the second bypassflow passage 17 and hence, the pressure difference between thesecondary-side water passage 14 and the backpressure chamber 13 isinstantly reduced. Along with the reduction of pressure difference, theopen/close valve 12 is moved to the upper back pressure chamber 13 sideand hence, the water inlet 10 and the secondary-side water passage 14are communicated with each other whereby the water flows in thesecondary-side water passage 14 from the water inlet 10 due to the waterpressure and, further, the water is supplied to the toilet bowl 3 fromthe water outlet 11.

The apparatus body 6 includes a power generating unit 23 which generateselectric power by making use of water which flows in the secondary-sidewater passage 14.

That is, the apparatus body 6 forms, as shown in FIG. 4 to FIG. 6, acircular opening portion 24 in a lower left side portion thereof and asupport recessed portion 25 in an inner wall thereof which faces theopening portion 24 in an opposed manner. A distal end portion of thepower generating unit 23 which is inserted from the opening portion 24is supported on the support recessed portion 25 and, at the same time, amidst portion of the power generating unit 23 is supported on theopening portion 24.

The power generating unit 23, as shown in FIG. 4 to FIG. 7, isconstituted of a holder 26, an impeller 27, an intermediate cover 28, acoil 29 and a cover 30 in a separable manner.

The holder 26 forms a cylindrical portion 32 having an arcuate crosssection on an approximately rectangular-shaped flange 31, anapproximately disc-shaped shaft support portion 33 is formed on a distalend of the cylindrical portion 32, a proximal end portion of a rotatingshaft 34 is mounted on a center of the shaft support portion 33. In thedrawing, numeral 35 indicates bolt holes.

Further, the holder 26 mounts an approximately cylindrical shapedimpeller 27 on a rotating shaft 34 thereof in a rotatable manner.

The impeller 27 mounts a rotating cylindrical portion 37 on a distal endside of a circular cylindrical portion 36 thereof having a circularcross section in a projecting manner, wherein a diameter of the rotatingcylindrical portion 37 is set smaller than a diameter of the cylindricalportion 36. Further, eight curved blades 38 are formed on a distal endside of the cylindrical portion 36 in a state that the curved blades 38extend in the radial outer direction and are also spaced apart from anouter peripheral surface of the rotating cylindrical portion 37. Adisc-shaped end plate 39 is formed on distal ends of the rotatingcylindrical portion 37 and the blades 38.

By forming a space between the outer peripheral surface of the rotatingcylindrical portion 37 and inner end portions of the blades 38, theimpeller 27 forms clearances 40 which allow water to pass therethroughinside the blades 38.

Further, the impeller 27 forms spiral-shaped grooves 41 having thespiral direction opposite to the rotating direction of the impeller 27on the outer peripheral surface of the cylindrical portion 36. Further,on the proximal end side of a cylindrical portion 36, the impeller 27mounts a circular supporting cylindrical portion 42 having a diametersmaller than a diameter of cylindrical portion 36 is mounted in aprojecting manner. A cylindrical magnet 43 having a circular crosssection is mounted on the supporting cylindrical portion 42.

The magnet 43 alternatively and continuously forms north poles and southpoles on an outer peripheral portion thereof.

Further, in the impeller 27, the magnet 43 is rotatably engaged in theintermediate cover 28.

The intermediate cover 28 forms a cylindrical portion 45 on a centerportion of an annular disc portion 44, wherein the magnet 43 is engagedin the cylindrical portion 45. A distal end portion of the rotary shaft34 is supported on a center portion of the distal end of the cylindricalportion 45. In the drawing, numeral 46 indicates tongues which areformed on an outer periphery of the annular disc portion 44 and numeral47 indicates through holes formed in the tongues 46.

Further, with respect to the intermediate cover 28, a coil 29 is engagedon an outer peripheral portion of the cylindrical portion 45.

The coil 29 is formed annularly, wherein the cylindrical portion 45 ofthe intermediate cover 28 is engaged in the center through hole 48 ofthe coil 29 and an output terminal 49 is formed on an outer portion ofthe coil 29.

The coil 29 is hermetically covered with the intermediate cover 28 andthe cover 30.

The cover 30 forms a cylindrical portion 51 on a center of anapproximately rectangular flange portion 50 and the coil 29 is engagedin the cylindrical portion 51. In the drawing, numeral 52 indicatesthrough holes.

The cover 30 is mounted on a flange 31 of the holder 26 together withthe intermediate cover 28 using bolts 53.

The power generating unit 23 having such a constitution is inserted intothe apparatus body from the opening portion 24 formed in the apparatusbody 6, a distal end portion of the power generating unit 23 issupported on the inside of the apparatus body 6, and the flange 31 ofthe holder 26 is detachably mounted on a flange 54 formed on an outerperipheral portion of the opening 24 using bolts 55.

Due to such a constitution, the power generating unit 23 can be easilymounted or dismounted from the apparatus body 6 and hence, theassembling property of the toilet bowl flushing apparatus can beenhanced and, at the same time, the maintenance property of the powergenerating unit 23 can be enhanced.

Further, since the distal end portion of the power generating unit 23 issupported in the inside of the apparatus body 6, it is possible toassemble the power generating unit 23 to the apparatus body 6 in astable manner whereby the rotating shaft 34 can be accurately arrangedin place in the flow passage of the apparatus body 6.

Further, in a state that the power generating unit 23 is mounted on theapparatus body 6, the rotating shaft 34 extends in the directionorthogonal to the direction of water flow in the flow passage 56 formedin the inside of the apparatus body 6, the impeller 27 which is drivenby the water flow is mounted on the rotating shaft 34, and the coil 29is arranged at a position where the coil 29 faces the magnet 43 which isintegrally rotated in an interlocking manner with the impeller 27.

Due to such a constitution, in the power generating unit 23, water whichflows in the flow passage 56 impinges on the distal end portions of theblades 38 of the impeller 27 so as to rotate the impeller 27, and themagnet 43 is interlockingly rotated whereby the power generation isperformed due to a cooperative action of the magnet 43 and the coil 29.

Further, in such an operation, water which impinges on the distal endportions of the blades 38, thereafter, flows not only toward the outsidethan the distal end of the blades 38 but also toward the proximal endportion of the blades 38. However, water which flows into the proximalend portion of the blades 38 passes through the clearance 40 which isformed in the inner portions of the blades 38 in a state that theclearance 40 allows water to pass therethrough and is smoothlydischarged from the impeller 27.

Accordingly, the possibility that water which flows toward the proximalend portions of the blades 38 obstructs the rotation of the impeller 27can be eliminated and hence, the power generation amount due to thepower generating unit 23 can be increased. Further, the increase ofpressure loss in the apparatus body 6 attributed to the insertion of thepower generating unit 23 can be reduced and hence, it is unnecessary toexpand the flow passage 56 outside the impeller 27 where by toilet bowlflushing device 1 can be miniaturized.

It is preferable to form the clearance 40 such that a ratio(width/radius) between a width of the clearance 40 and a radius of theimpeller 27 falls within a range of 0.1 to 0.8. It is more preferable toform the clearance 40 such that the ratio falls within a range of 0.2 to0.5. This is because that, as shown in FIG. 8, when the ratio betweenthe width of the clearance 40 and the radius of the impeller 27 fallswithin a range of 0.2 to 0.5, an output attributed to the impeller 27substantially reaches a peak and hence, it is possible to approximatethe power generation amount by the power generating unit 23 to a maximumvalue. Further, when the ratio between the width of the clearance 40 andthe radius of the impeller 27 falls within a range of 0.1 to 0.8, it ispossible to ensure one half of the maximum value (0.25W) or more as theoutput attributed to the impeller 27.

Here, FIG. 8 shows a result when water flows at a flow rate of 11L/min.In series A, the clearance between the rotating cylindrical portion 37and the blades 38 is changed by changing the diameter of the rotatingcylindrical portion 37 while fixing an outer blade diameter of theblades 38 to 20 mm and an inner diameter of the blades 38 to 13 mm.Further, in series B to D, the clearance between the rotatingcylindrical portion 37 and the blades 38 is changed by changing theinner diameter of the blades 38 within a range of 10 mm to 18 mm.Further, peak values which exhibit the highest outputs when therotational speed is changed by changing a load applied to the rotationalshaft 34 are plotted. Here, in the series A to D, it is assumed that theblades 38 are formed of eight arcuate blades.

Further, in a state that the generating unit 23 is mounted on theapparatus body 6, the magnet 43 is arranged in the inside of the flowpassage 56, while the coil 29 is arranged outside the flow passage 56which is hermetically partitioned from the flow passage 56 by anintermediate cover 28.

Due to such a constitution, there is no possibility that the coil 29 isimmersed in water and hence, it is possible to prevent erroneousoperations and troubles of the power generating unit 23 attributed tothe erosion and the short-circuiting of the coil 29.

Further, in the power generating unit 23, on an outer peripheral surfaceof the cylindrical portion 27 of the impeller 27, the grooves 41 whichhave a spiral shape so as to generate a water flow which pushes backforeign substances such as iron rusts toward the blade 38 side due tothe rotation of the impeller 27 are formed. Due to such a constitution,it is possible to prevent the movement of the foreign substance such asthe iron rusts from the flow passage 56 to the magnet 43. That is, byforming the grooves 41 between the blades 38 and the magnet 43, thepower generating unit 23 forms the intrusion suppression means 57 whichsuppresses the intrusion of the foreign substance such as iron rustsbetween the blades 38 and the magnet 43.

Further, by forming the intrusion suppression means 57 into a threadedshape having spear-headed distal ends, it is possible to finely crushthe foreign substance such as iron rusts which intrude into theintrusion suppression means 57 by a rotating force and hence, it ispossible to prevent in advance a phenomenon that the rotation of theimpeller 27 is stopped due to the clogging of the foreign substance inthe intrusion suppression means 57.

In this manner, the power generating unit 23 includes the intrusionsuppression means 57 which suppresses the intrusion of iron dusts or thelike between the blades 38 and the magnet 43 and hence, it is possibleto prevent the adhesion of the iron rusts or the like to the magnet 43.Further, due to the formation of the spear-headed distal ends on theintrusion suppression means 57, it is possible to suppress the cloggingof the iron rust or the like in the intrusion suppression means 57 andhence, erroneous operations and troubles of the power generating unit 23attributed to the adhesion of the impeller 27 can be prevented inadvance.

Particularly, since the intrusion suppression means 57 is constituted ofthe grooves 41 which are spirally formed on the outer periphery of theimpeller 27 in a state that the groove forming direction is opposite tothe rotational direction of the impeller 27, it is possible to easilyform the intrusion suppression means 57 between the blades 38 and themagnet 43 and hence, the power generating unit 23 can be designedcompactly.

Further, in the toilet bowl flushing apparatus 1, the power generatingunit 23 is arranged on a center line of the water inlet port 10 formedin the apparatus body 6 in a plan view in a state that the powergenerating unit 23 faces the water inlet port 10 in an opposed manner,and a rotating shaft 34 of the power generating unit 23 is arranged on acenter line of the flow passage 59. Due to such a constitution, theprojection amounts of the power generating unit 23 in the fore-and-aftdirections with respect to the flow passage 59 are set equal. The flowpassage 59 has the center line thereof aligned with the water inlet port10 and the water outlet port 11 formed in the apparatus body 6. Further,the toilet bowl flushing apparatus 1 accommodates the water inlet port10, the water outlet port 11 and the power generating unit 23 at thecenter in the fore-and-aft direction of the casing 5.

Accordingly, as shown in FIG. 9( a) and FIG. 9( b), even when theapparatus body 6 is reversed in the fore-and-aft direction, there is nochange in the handling of the apparatus body 6 with respect to the waterinlet port 10 and the water outlet port 11. Further, there is nopossibility that the casing 5 which houses the apparatus body 6 projectsin the frontward and rearward directions and hence, irrespective of theposition of the water supply pipe 2 which is connected to the waterinlet port 10, it is possible to favorably mount the power generatingunit 23 on the apparatus body 6 whereby the installation property of thetoilet bowl flushing device 1 can be enhanced.

That is, as shown in FIG. 2 and FIG. 9, when the water supply pipe 2 isarranged on the right side of the toilet bowl flushing device 1, theapparatus body 6 is housed in the inside of the casing 5 in a state thatthe water inlet port 10 of the apparatus body 6 is directed to the rightside and the water inlet port 10 and the water supply pipe 2 areconnected to each other. On the other hand, when the water supply pipe 2is arranged on the left side of the toilet bowl flushing device 1, theapparatus body 6 is housed in the inside of the casing 5 in a state thatthe water inlet port 10 of the apparatus body 6 is directed to the leftside and the water inlet port 10 and the water supply pipe 2 areconnected to each other. In this case, it is sufficient to mount theapparatus body 6 in a reverse manner such that the positionalrelationship between the front cover 8 and the rear cover 9 is reversedin the fore-and-aft direction while maintaining the upper cover 7 andthe control unit 20 housed in the upper cover 7.

Further, with respect to the toilet bowl flushing device 1, as shown inFIG. 5, in a state that the power generating unit 23 is mounted on theapparatus body 6, a clearance 59 is formed between outer peripheries ofthe blades 38 and an inner wall 58 of the flow passage 59. Thisclearance 59 is larger than a clearance between the outer peripheries ofthe blades 38 and the cylindrical portion 32, thus forming a flowpassage which does not receive the pressure loss attributed to theimpeller 27.

Accordingly, the toilet bowl flushing device 1 allows the inflow of anamount of water sufficient to generate power to the impeller 27 andallows a portion of water which flows in the flow passage 56 to flow outthrough the clearance 59 between the outer peripheries of the blades 38and the inner wall 58 of the flow passage 56 and hence, the pressureloss in the flow passage 56 can be suppressed.

Further, since the cylindrical portion 32 is formed along the outerperipheries of the blades 38, the power generating unit 23 canaccurately regulate an amount or an inflow angle of water which rotatesthe impeller 27 by impingement on the blades 38 by changing the shape ofthe cylindrical portion 32 whereby it is possible to obtain the desiredpower generation amount using the power generating unit 23.

Further, in the toilet bowl flushing device 1, a guide member 60 whichguides water toward the impeller 27 is formed inside the flow passage 56of the apparatus body 6 and the guide member 60 is contiguously formedwith the cylindrical portion 32 of the power generating unit 23.

Also due to such a constitution, it is possible to accurately regulatean amount of water which flows in the impeller 27 whereby it is possibleto obtain the desired power generation amount using the power generatingunit 23.

Although cylindrical portion 32 and the guide member 60 are formed onlyon one side of the flow passage 56 as shown in FIG. 5, cylindricalportions 32 and guide members 60 may be formed on both sides of the flowpassage 56 as shown in FIG. 10.

That is, in the toilet bowl flushing apparatus 1 shown in FIG. 10, acylindrical portion 61 and a guide member 62 are formed at positionswhere the cylindrical portion 61 and the guide member 62 face the ecylindrical portion 32 and the guide member 60 with the rotating shaft34 therebetween.

In this manner, by providing the guide members 60, 62 at the positionswhere the guide members 60, 62 face each other with the cylindricalportions 32, 61 and the rotating shaft 34 therebetween, the impeller 27is rotated using water which flows through the clearance between thecylindrical portions 32, 61 and the guide members 60, 62 and hence, itis possible to surely generate power by the power generating unit with asmall amount of water.

(Power Generating Unit for Indoor Facility)

FIG. 12 and FIG. 13 show a power generating unit 101 for an indoorfacility which constitutes the water supply apparatus according to thepresent invention. The power generating unit 101 for an indoor facilityis configure to be directly connected to a midst portion of a servewater pipe.

As shown in FIG. 12 and FIG. 13, the power generating unit 101 for anindoor facility includes a first casing 102 having a straightcylindrical shape which forms an opening 102 a in a center portion of aside wall thereof, wherein a cylindrical portion 102 b extends in theoutward radial direction from the opening 102 a, and an outer flange 102c is formed on an end portion of the cylindrical portion 102 b.

Further, the power generating unit 101 for an indoor facility includes asecond casing 103 which has a cylindrical portion 103 a and an outerflange 103 b which is formed on one end of the cylindrical portion 103a, wherein the cylindrical portion 103 a is inserted into thecylindrical portion 102 b. Further, the cylindrical portion 103 a isbrought into contact with the cylindrical portion 102 b, while the outerflange 103 b is brought into contact with the outer flange 102 c.

Further, the power generating unit 101 for an indoor facility includes athird casing 104 which has a bottomed cylindrical portion 104 a and anouter flange 104 b which is formed on an open end of the bottomedcylindrical portion 104 a, wherein an inner space of the bottomedcylindrical portion 104 a is communicated with an inner space of thecylindrical portion 103 a and the outer flange 104 b is brought intocontact with the outer flange 103 b.

Further, the power generating unit 101 for an indoor facility includes acap 105 which has a bottomed cylindrical portion 105 a and an outerflange 105 b which is formed on an open end of the bottomed cylindricalportion 105 a, wherein the cap 105 houses the third casing 104. Further,the outer flange 105 b is brought into contact with the outer flange 103b and these outer flanges 103 b, 105 b are fixed to the outer flange 102c by bolts 106.

Further, the second casing 103 is clamped between the outer flange 102 cof the first casing 102 and the outer flange 105 b of the cap 105 andhence, the second casing 103 is fixed to the first casing 102. Further,the third casing 104 is clamped between the outer flange 103 b of thesecond casing 103 and the bottom portion of the cap 105 and hence, thethird casing 103 is fixed to the second casing 103.

Further, a contact portion between the cylindrical portion 102 b and thecylindrical portion 103 a is sealed by an O-ring 107, while a contactportion between the outer flange 103 b and the outer flange 104 b issealed by an O-ring 108.

Further, the first casing 102, the second casing 103 and the thirdcasing 104 are integrally assembled thus forming a casing 109.

Further, a flow passage 110 is formed of a main flow passage 110 aextending approximately upright which is formed in the inside of thefirst casing 102 and a chamber 110 b which is formed in the inside ofthe second casing 103 and in the inside of the third casing 104 and isbranched from the main flow passage 110 a and extends in the radialoutward direction.

The impeller 111 is arranged in the inside of the main flow passage 110a.

A rotary shaft 111 a of the impeller 111 is extended in the directionorthogonal to the extending direction (water flow direction) of the mainflow passage 110 a. Disc-like end plates 111 b, 111 c are fixed to bothends of the rotating shaft 111 a in a state that the end plates 111 b,111 c are spaced apart from each other. A plurality of rectangularplate-like curved blades 111 d are arranged in a state that the blades111 d are extended from the peripheral portion of the end plate 111 b tothe peripheral portion of the end plate 111 c and in a circumferentiallyspaced-apart manner. Both ends of the curved blades 111 d are fixed tothe end plate 111 b and the end plate 111 c.

A clearance S101 is formed between the curved blades 111 d and therotating shaft 111 a.

Further, the rotating shaft 111 a of the impeller 111 is offset in theradial and outward direction from a center axis of the main flow passage110 a immediately upstream of the impeller 111 with respect to the waterflow. Accordingly, a clearance S102 between a side wall of the firstcasing 102 and the curved blades 111 d in the offset direction of therotating shaft 111 a is narrow, while a clearance S103 between the sidewall of the first casing 102 and the curved blades 111 d in thedirection opposite to the offset direction of the rotating shaft 111 ais wide.

A guide member 112 is inserted into and fixed to an upstream-side endportion of the main flow passage 110 a and to the narrow-width gap S102side in a state that the guide member 112 approaches the impeller 111.Further, an oblique surface 112 a which extends toward the large-widthgap S103 from the upstream side is formed in the guide member 112.Further, the oblique surface 112 a extends toward the large-width gapS103 after getting over the position right above the impeller rotatingshaft 111 a. Further, due to the provision of the guide member 112, themain flow passage 110 a is squeezed at the immediately upstream of theimpeller 111.

On the other hand, a guide member 112′ is inserted into and fixed to andownstream-side end portion of the main flow passage 110 a and to thenarrow-width gap S102 side in a state that the guide member 112′approaches the impeller 111. Further, an oblique surface 112 a′ whichextends toward the large-width gap S103 from the downstream side isformed in the guide member 112′. Further, the oblique surface 112 a′extends toward the large-width gap S103 after getting over the positionright below the rotating shaft 111 a of the impeller 111.

Further, the rotating shaft 111 a of the impeller 111 is offset in theradial outward direction from the center axis of the main flow passage110 a and the guide members 12, 12′ are arranged and hence, with respectto the water flow of the main flow passage 110 a, an immediatelyupstream portion and an immediately downstream portion of the impeller111 are directed toward an outer peripheral portion of the impeller 111and the large-width gap S103.

Further, the rotating shaft 111 e which is fixed to the end plate 111 cextends coaxially with the rotating shaft 111 a in the inside of thechamber 110 b. To a portion of the rotating shaft 111 e which extends inthe inside of the bottomed cylindrical portion 104 a of the third casing104, an annular magnet 113 which has a plurality of magnetic poles inthe circumferential direction in a spaced apart manner is fixed. Themagnet 113 is designed such that the radial outer end portion of themagnet 113 alternately and circumferentially repeats the N pole and theS pole.

Further, an end portion of the rotating shaft 111 a at an end plate 111b side and an end portion of the rotating shaft 111 a at a magnet 113side are respectively supported by bearings.

Further, a coil 114 is disposed outside the third casing 104, that is,in the inside of the cap 105 in a state that the coil 114 wraps abottomed cylindrical portion 104 a of the third casing 104. The coil 114faces the magnet 113 while sandwiching the bottomed cylindrical portion104 a therebetween thus allowing a magnetic flux of the magnet 113 topass the coil 114.

The above-mentioned power generating unit 101 for an indoor facilityhaving the above-mentioned constitution is interposed between a faucet100 for an indoor facility which is turned on to allow a water flow toflow upon the energizing of an electromagnetic valve not shown in thedrawing and automatically stops the water flow after a lapse of a giventime based on trigger signals from various sensors such as a human bodydetection sensor, a waste detection sensor, an odor sensor and the like,and a vacuum breaker 200 which is arranged downstream of the faucet 100for an indoor facility. That is, one end portion of the first casing 102in which a guide member 112 is inserted is connected to the downstreamside of the faucet 100 for an indoor facility by way of a flange, whileanother end of the first casing 102 is connected to the upstream end ofthe vacuum breaker 200. The guide member 100 a having an oblique surface100 a′ which is connected with an oblique surface 112 a of the guidemember 112 on a coplanar plane is inserted into and fixed to adownstream end of the faucet 100 for an indoor facility.

The casing 109 of the power generating unit 101 for an indoor facilityforms a portion of a service water pipe, while the vacuum breaker 200 isconnected with a flushing toilet bowl not shown in the drawing by way ofa pipe not shown in the drawing.

Next, the manner of operation of the power generating unit 101 for anindoor facility having the above-mentioned constitution is explained.

In the faucet 100 for an indoor facility, the electromagnetic valvewhich is not shown in the drawing is energized and hence, a water flowwhich is allowed to flow upon actuation of the electromagnetic valveflows into the main flow passage 110 a of the power generating unit 101for an indoor facility while being guided by the oblique surface 100 a′of the guide member 100 a. The water flow is directed toward an outerperipheral portion of the impeller 111 and also is directed toward thelarge-width clearance S103 while being guided by the oblique surface 112a of the guide member 112 which is connected with the oblique surface100 a′ on a coplanar plane

The water flow which flows into the outer peripheral portion of theimpeller 111 impinges on the curved blades 111 d on the large-widthclearance S103 side and rotatably drives the impeller 111. The impeller111 rotatably drives the magnet 113.

Then, due to a change of the magnetic flux of the magnet 113 whichpasses through the coil 114, an electromotive force is generated in thecoil 114. The power generated in the coil 114 is, directly or afterbeing stored in a secondary cell or a capacitor, utilized as a portionof drive power for the electromagnetic valve which is not shown in thedrawing provided to the faucet 100 for an indoor facility or utilized asa portion of drive power for various kinds of sensors, a portion ofdrive power of various kinds of control circuits, a portion of drivepower of various kinds of functional members such as a lamp or anelectrolytic vessel which are provided to the indoor facility.

Further, the water flow which rotatably drives the impeller 111 flowsout from the outer periphery of the impeller 111 and, flows into avacuum breaker 200 from the power generating unit 101 for an indoorfacility through the main flow passage 110 a, flows into the flushingtoilet bowl which is not shown in the drawing, and is served fordischarging a waste in the toilet bowl from the toilet bowl.

In the power generating unit 101 for an indoor facility having theabove-mentioned constitution, the magnet 113 which is rotatably drivenby the impeller 111 is arranged in the inside of the flow passage 110and the coil 114 which faces the magnet 113 is arranged outside the flowpassage 110. Accordingly, it is unnecessary to allow one end of therotary shaft 111 e of the impeller 111 to penetrate the surrounding wallof the flow passage 110 and to extend toward the outside of the flowpassage 110 and it is also unnecessary to provide a slide contactportion between the rotary shaft 111 e and a sealing member. As aresult, it is possible to suppress the leaking of water to the outsideof the flow passage 110 thus suppressing a phenomenon that the coil 114is splashed with water.

Further, in the main flow passage 110 a, a portion immediately upstreamof the impeller 111 and a portion immediately downstream of the impeller111 with respect to the water flow are directed toward the outerperiphery of the impeller 111 and hence, the water flow flows into theouter periphery of the impeller and flows out from the outer periphery.As a result, the water flow in the direction of the rotary shaft 111 aof the impeller 111 is largely suppressed, and the water flow in thedirection of the magnet 113 which is engaged with the rotary shaft 111 aof the impeller 111 is also largely suppressed and hence, the phenomenonthat the magnet 113 is splashed with water can be largely suppressed,and the erosion of the magnet 113 and the adhesion of foreign substancesto the magnet 113 are largely suppressed.

Further, in the power generating unit 101 for an indoor facility, sincethe main flow passage 110 a in the vicinity of the impeller 111 extendsapproximately straightly, the bending of the water flow is suppressedwhereby the pressure loss is suppressed.

Further, in the power generating unit 101 for an indoor facility, therotary shaft 111 a of the impeller 111 is offset from the center axis ofthe main flow passage 110 a immediately upstream of the impeller 111 inthe outward radial direction with respect to the water flow and, thelarge-width clearance S103 is formed between the outer periphery of theimpeller 111 on a side opposite to the above-mentioned offset directionand a surrounding wall of the main flow passage 110 a which faces theouter periphery and, further, the main flow passage 110 a immediatelyupstream of the impeller 111 is directed toward the outer peripheralportion of the impeller 111 and toward the large-width clearance S103.Accordingly, only the water flow which is necessary for generating thepower is introduced to the impeller 111 and, on the other hand, theremaining water flow is introduced to the large-width clearance S103 andhence, the generation of undesired pressure loss is suppressed.

Further, in the power generating unit 101 for an indoor facility, sincethe clearance S101 is formed between the curved blades 111 d and therotary shaft 111 a of the impeller 111, a state that the water flowdwells above the curved blade 111 d is suppressed and hence, therotation resistance of the impeller 111 is suppressed whereby thepressure loss attributed to the impeller 111 is suppressed.

Further, in the power generating unit 101 for an indoor facility, themain stream passage 110 a is squeezed at the immediately upstream of theimpeller 111 and hence, a flow speed of the water flow which impinges onthe impeller 111 is increased thus enhancing the power generationefficiency.

Further, in the power generating unit 101 for an indoor facility, byfixing the magnet 113 to the rotary shaft 111 e of the impeller 111, thepower transmission loss which occurs when the power is transmitted fromthe rotary shaft 111 e to the magnet 113 is suppressed and hence, thepower generation efficiency is enhanced. Further, since a powertransmission mechanism is not interposed between the rotary shaft 111 eand the magnet 113, the power generating unit 101 for an indoor facilitycan be miniaturized.

Further, in the power generating unit 101 for an indoor facility, sincethe casing 109 is configured to form a portion of the water pipe, byincorporating or assembling the power generating unit 101 for an indoorfacility into the service water pipe, it is possible to easily performthe power generation and to convert the hydraulic energy which has beenwasted into the electric energy efficiently.

Further, in the power generating unit 101 for an indoor facility, thewater flow is directed toward the outer peripheral portion of theimpeller 111, and hence a torque which the water flow applies to theimpeller 111 can be increased.

Accordingly, the power generating unit 101 for an indoor facilityquickly rises at the time of starting and hence, it is possible to startthe power generation immediately after the water flow is allowed toflow. Further, when the power generating unit 101 for an indoor facilityis combined with the faucet 100 for an indoor facility which allows thewater flow to flow in response to the energizing of the electromagneticvalve not shown in the drawing and automatically stops the water flowafter the lapse of a given time, the power generating unit 101 for anindoor facility can surely generate power within a given time from thepoint of time that the water flow is allowed to flow to the point oftime that the water flow is stopped.

Accordingly, even when the time from the point of time that the waterflow is allowed to flow to the point of time that the water flow isstopped is short, to be more specific, even when the time is equal to orless than 1 minute, the power generating unit 101 for an indoor facilitycan efficiently generate power and supply at least a portion of drivepower for the above-mentioned electromagnetic valve.

Further, in the power generating unit 101 for an indoor facility, sincethe water flow which is directed toward the outer peripheral portion ofthe impeller 111 efficiently applies a force to the blades 111 d in thevicinity of the outer periphery having a large peripheral speed andhence, the pressure loss attributed to the impeller 111 is small.Further, a large-width clearance S103 is formed close to the outerperipheral portion of the impeller 111 and the clearance S101 is formedbetween the rotary shaft 111 a and the blades 111 d of the impeller 111and hence, the flow resistance of the impeller 111 is small, the rotaryresistance is small and the pressure loss attributed to the impeller 111is small. Accordingly, it is possible to allow the water flow on thedownstream side of the impeller 111 to have a water pressure necessaryfor waste transfer, specifically, a water pressure equal to or more than0.02 MPa.

Further, in the power generating unit 101 for an indoor facility,functional members such as the main flow passage 110 a, the impeller111, the magnet 113 and the coil 114 are designed such that a valvevolume coefficient Cv which is expressed by a following formula (1)satisfies a formula (2).Cv=(N×Q)/√(ΔP)  (1)Cv≧0.1267×Q  (2)

Here, N is 0.0219, Q is a flow rate (L/minute) of the water flow whichflows in the power generating unit for an indoor facility, ΔP (MPa) isthe pressure loss of the power generating unit for an indoor facility.

The valve volume coefficient Cv expressed by the formula (1) is aconstant which defines the relationship between the pressure differenceΔP between an inlet and an outlet of the valve and the flow rate offluid which flows through the valve. The valve volume coefficient Cv isthe constant which is defined by a shape and a size of the valve.

Here, when the valve volume coefficient satisfies the formula (2), therelationship ΔP≦0.03 MPa is established. Assuming the power generatingunit for an indoor facility 1 as a type of valve, when the valve volumecoefficient Cv of the power generating unit 101 for an indoor facilitysatisfies the formula (2), the pressure loss ΔP of the power generatingunit for an indoor facility 1 becomes equal to or less than 0.03 MPa.Since the terminal water pressure of the water pipe to which the indoorfacility is connected is generally equal to or more than 0.05 MPa,provided that the valve volume coefficient Cv of the power generatingunit 101 for an indoor facility satisfies the formula (2), it ispossible to allow the water flow on the downstream side of the powergenerating unit 101 for an indoor facility to have the water pressureequal to or more than 0.02 MPa which is necessary for the wastetransfer.

The power generating unit 101 for an indoor facility in which the valvevolume coefficient Cv satisfies the formula (2) is suitably combinedwith an indoor facility having the relatively small flow rate or anindoor facility which can be driven under the low pressure.Specifically, the power generating unit 101 for an indoor facility issuitably combined with an indoor facility such as a bathroom faucet, awash-basin faucet, a kitchen faucet, a tank-equipped toilet bowl or aurinal, or a human part cleaning device.

Further, when the valve volume coefficient Cv of the power generatingunit 101 for an indoor facility satisfies a following formula (3), thepressure loss ΔP of the power generating unit 101 for an indoor facilitybecomes equal to or less than 0.02 MPa and hence, it is possible toallow the water flow on the downstream side of the power generating unit101 for an indoor facility to have the water pressure equal to or morethan 0.03 MPa.Cv≧0.155×Q  (3)

The power generating unit 101 for an indoor facility in which the valvevolume coefficient Cv satisfies the formula (3) is also suitablycombined with a service-water direct-pressure type toilet bowl or aurinal, a bath-room shower, a bubble-mixing type wash-basin faucet orkitchen faucet in addition to the above-mentioned indoor facilities.

Further, when the valve volume coefficient Cv of the power generatingunit 101 for an indoor facility satisfies a following formula (4), thepressure loss ΔP of the power generating unit 101 for an indoor facilitybecomes equal to or less than 0.01 MPa and hence, it is possible toallow the water flow on the downstream side of the power generating unit101 for an indoor facility to have the water pressure equal to or morethan 0.04 MPa.Cv≧0.2194×Q  (4)

The power generating unit 101 for an indoor facility in which the valvevolume coefficient Cv satisfies the formula (4) is also suitablycombined with an indoor facility which has a relatively large flow rateand requires a high pressure to drive in addition to the above-mentionedindoor facilities.

In the power generating unit 101 for an indoor facility, as shown by achain line in FIG. 13, an outer flange 103 b of a second casing 103 maybe extended in the inward radial direction thus forming a squeezedportion S104 between the main flow passage 110 a which incorporates theimpeller 111 therein and a portion of the chamber 110 b whichincorporates the magnet 113 therein.

In this case, the intrusion of water to the vicinity of the magnet 113is suppressed and the splashing of water to the magnet 113 is suppressedand the erosion of the magnet 113 or the adhesion of foreign substanceson the magnet 113 is suppressed.

Further, it is possible to replace the extending portion of the outerflange 103 b in the above-mentioned inward radial direction with a net.

In this case also, the intrusion of water to the vicinity of the magnet113 is suppressed and the splashing of water to the magnet 113 issuppressed and the erosion of the magnet 113 or the adhesion of foreignsubstances on the magnet 113 is suppressed.

Further, in the power generating unit 101 for an indoor facility, asshown in FIG. 14, it is possible to dispose a transmission 115 in theinside of the chamber 110 b and to engage the magnet 113 with theimpeller 111 by way of the transmission 115.

In the power generating unit 101 for an indoor facility, an outputcharacteristics W1 of the impeller 111 and an input characteristics W2of the power generator formed with the magnet 113 and the coil 114 aregenerally as shown in FIG. 15.

Accordingly, when the impeller 111 and the above-mentioned powergenerator are connected, the power generator is operated at a point atwhich the output of the impeller 111 and the input of the powergenerator are balanced, that is, a crossing point P of W1 and W2.

Here, by engaging the magnet 113 with the impeller 111 by way of thetransmission 115 and by moving the input characteristics W2′ of thepower generator based on rotational speed of the impeller 111 leftwardas shown by a chain line in FIG. 15, it is possible to move the crossingpoint of W1 and W2′ and, furthermore, the operation point of the powergenerator to a maximum output point M of the impeller 111.

Since the output of the power generator is increased or decreasedcorresponding to the increase or the decrease of the input of the powergenerator, by moving the operation point of the power generator to themaximum output point M of the impeller 111, the power generator isdriven with the maximum output of the impeller 111 and hence, it ispossible to acquire the maximum output from the power generator. As aresult, the power generating efficiency of the power generating unit 101for an indoor facility is enhanced. Further, it is possible to change anelectric power output of the power generating unit 101 for an indoorfacility when necessary without changing the designing of the main flowpassage 110 a, the impeller 111, the magnet 113 and the coil 114.

The number of curved blades 111 d of the impeller 111 is favorably equalto or more than 4 and equal to or less than 20. This is because that,since energy which one curved blade 111 d receives from the water flowis limited, when the number of curved blades 111 d is less than 4, it isdifficult to receive the sufficient energy for power generation from thewater flow. On the other hand, another reason is that, when the numberof the curved blades 111 d is more than 20, an interval between theblades in the circumferential direction becomes small and hence, theflow resistance is increased whereby the energy acquisition efficiencyis lowered.

As shown in FIG. 16, the cross-sectional shape of the curved blades 111d of the impeller 111 is favorably a curve protruding in the water flowdirection as shown by a white-matted arrow. The energy acquisitionefficiency with the curved blades is higher than the energy acquisitionefficiency with planar blades.

Further, when the power generating unit 101 for an indoor facility isused in combination with an indoor facility having relatively small flowrate or an indoor facility which can be driven under low pressure orwhen necessary in arranging a flow passage, it is possible to curve themain flow passage 110 a in the vicinity of the impeller 111 along theouter periphery of the impeller 111. Further, it is possible to arrangethe power generating unit 101 for an indoor facility at the upstream ofthe faucet 100 for an indoor facility. Further, it is possible to omitthe vacuum breaker 200.

As shown in FIG. 17, it is possible that the rotary shaft 111 a and therotary shaft 111 e of the impeller 111 are integrated to form a rotaryshaft 111 a′, one end of the rotary shaft 111 a′ is fixed to the firstcasing 102 and another end of the rotary shaft 111 a′ is fixed to thethird casing 104, a boss 111 f which is fitted in a rotatable andslidable manner on the rotary shaft 111 a′ is provided, an end plate 111b′ is fixed to one end of the boss 111 f while an end plate 111 c′ isfixed to another end of the boss 111 f and the magnet 113′ is fixed tothe end plate 111 c′. A bearing 111 g is arranged between the magnet113′ and the rotary shaft 111 a′. In this case, the curved blades 111 dare rotated around the rotary shaft 111 a′ and the magnet 113′ isrotated along with the rotation of the curved blades 111 d.

INDUSTRIAL APPLICABILITY

The water supply apparatus according to the present invention isconstituted by disposing the apparatus body in the midst of the flowpassage for supplying water to the indoor facility and by installing thepower generating unit in the apparatus body.

Further, the power generating unit includes the rotating shaft extendedin the direction orthogonal to the water flow direction of the flowpassage, the impeller mounted on the rotating shaft and rotated by thewater flow, the magnet rotated interlockingly with the impeller, and thecoil arranged to face the magnet in the opposed manner, wherein theimpeller forms blades in the outward radial direction and formsclearances allowing water to pass the inside of the blades.

In the power generating unit according to the present invention, waterwhich flows in the flow passage impinges on the distal end portions ofthe blades so as to rotate the impeller, and the magnet isinterlockingly rotated whereby the power generation is performed due tothe cooperative action of the magnet and the coil.

Further, in such an operation, water which impinges on the distal endportions of the blades, thereafter, flows not only toward the outsidethan the distal end of the blades but also toward the proximal endportion of the blades. However, water which flows into the proximal endportion of the blades passes through the clearance which is formed inthe inner portions of the blades and is smoothly discharged from theimpeller.

In this manner, in the present invention, since the clearance is formedbetween the blade and the rotary shaft, the possibility that water whichflows toward the proximal end portions of the blades obstructs therotation of the impeller can be eliminated whereby the power generationamount due to the power generating unit can be increased.

Further, in the present invention, it is unnecessary to expand the flowpassage outside the impeller for reducing the rotational resistance ofthe impeller whereby the water supply apparatus can be miniaturized.

Further, the power generating unit according to the present invention isinserted into the apparatus body from the opening portion formed in theapparatus body in a state that the distal end portion thereof issupported in the inside of the apparatus body.

Accordingly, the power generating unit can be easily mounted ordismounted from the apparatus body and hence, the assembling property ofthe water supply apparatus can be enhanced and, at the same time, themaintenance property of the power generating unit can be enhanced.

Further, since the distal end portion of the power generating unit issupported in the inside of the apparatus body, it is possible toassemble the power generating unit to the apparatus body in a stablemanner whereby the rotating shaft can be accurately arrange in place inthe flow passage of the apparatus body.

Further, in the power generating unit according to the presentinvention, while the magnet is arranged in the inside of the flowpassage, the coil is arranged outside the flow passage which ishermetically partitioned from the flow passage and hence, there is nopossibility that the coil is immersed in water whereby it is possible toprevent erroneous operations and troubles of the power generating unitattributed to the erosion and the short-circuiting of the coil inadvance.

Further, the power generating unit according to the present inventionincludes the intrusion suppression means which prevents the intrusion ofthe foreign substance such as iron rusts or the like between the bladesand the magnet and hence, it is possible to suppress the adhesion of theiron rusts or the like to the magnet 43. Further, by forming theintrusion suppression means into the thread shape having thespear-headed distal ends, it is possible to suppress the clogging of theiron rusts or the like in the intrusion suppression means 57 and hence,erroneous operations and troubles of the power generating unit 23attributed to the adhesion of the impeller 27 can be prevented inadvance.

Particularly, since the intrusion suppression means according to thepresent invention is constituted of the spiral grooves which arespirally formed on the outer periphery of the impeller in a state thatthe groove forming direction is opposite to the rotational direction ofthe impeller, it is possible to easily form the intrusion suppressionmeans between the blades and the magnet.

Further, according to the present invention, since the power generatingunit is arranged on the center line of the water inlet port formed inthe apparatus body, irrespective of the direction of the water supplypipe which is connected to the water inlet port, it is possible tofavorably mount the power generating unit on the apparatus body wherebythe installation property of the toilet bowl flushing device can beenhanced.

Further, according to the present invention, since the clearance isformed between the outer peripheries of the blades and the inner wall ofthe flow passage, it is possible to allow a portion of water which flowsin the flow passage to flow out through the clearance between the outerperipheries of the blades and the inner wall of the flow passage wherebythe pressure loss in the flow passage can be suppressed.

Further, in the power generating unit according to the presentinvention, since the cylindrical portion is formed along the outerperipheries of the blades, it is possible to accurately regulate anamount or an inflow angle of water which rotates the blades byimpingement on the blades by changing the shape of the cylindricalportion whereby it is possible to obtain the desired power generationamount using the power generating unit.

Further, according to the present invention, the guide member whichguides water toward the impeller is contiguously formed with thecylindrical portion and hence, it is possible to accurately regulate anamount of water which flows in the cylindrical portion whereby it ispossible to obtain the desired power generation amount using the powergenerating unit

Further, according to the present invention, since the guide memberwhich guides water toward the impeller is provided at the position wherethe guide member faces the cylindrical portion with the rotating shafttherebetween, the impeller is rotated with water which flows in throughthe clearance between the cylindrical portion and the guide memberwhereby the power can be surely generated using the power generatingunit with a small water quantity.

1. A water supply apparatus in which an apparatus body is disposed in amidst of a flow passage for supplying water to an indoor facility and apower generating unit is installed in the apparatus body, the powergenerating unit comprising; a rotating shaft extended in the directionperpendicular to the water flow direction of the flow passage; animpeller mounted on the rotating shaft and rotated by a water flow; aholder having a cylindrical portion with an arcuate cross section alongthe impeller and having a shaft support portion which supports aproximal end portion of the rotary shaft on a distal end portion of thecylindrical portion; a magnet rotated interlockingly with the impeller;and a coil arranged to face the magnet in an opposed manner wherein theholder in the power generating unit is mounted on a peripheral surfaceof an opening portion formed in the apparatus body in a state that theshaft support portion is inserted into the inside of the flow passagefrom the opening portion, the impeller forms blades in the outwardradial direction and forms clearances allowing water to pass the insideof the blades; a clearance is formed between outer peripheries of theblades and an inner wall of the flow passage, and the clearance is setlarger than a clearance between the outer peripheries of the blades andthe cylindrical portion for forming a flow passage which does notreceive a pressure loss attributed to the impeller.
 2. A water supplyapparatus according to claim 1, wherein the holder of the powergenerating unit has a distal end portion thereof supported in a statetat the distal end is fitted in an inner surface of the apparatus bodywhich faces the opening portion in an opposed manner.
 3. A water supplyapparatus according to claim 1 or 2, wherein the power generating unitincludes intrusion suppression means which suppresses the intrusion offoreign substances between the blades and the magnet.
 4. A water supplyapparatus according to claim 3, wherein the intrusion suppression meansis constituted by forming spear-headed thread-like grooves capable ofgenerating water flow which pushes back the foreign substance to theblade side due to the rotation of the impeller on an outer periphery ofthe impeller.
 5. A water supply apparatus according to claim 1 or 2,wherein a guide member which guides water toward the impeller is formedabove the cylindrical portion.
 6. A water supply apparatus according toclaim 5, wherein a second guide member which guides water toward theimpeller is arranged at a position where the second guide member facesthe guide member in an opposed manner with the rotary shaft sandwichedtherebetween.
 7. A water supply apparatus according to claim 1 or claim2, wherein in the power generating unit, the magnet is disposed insidethe flow passage and the coil is disposed outside the flow passage in ahermetically partitioned manner from the flow passage.
 8. A water supplyapparatus according to claim 1 or 2, wherein the power generating unitarranges the rotating shaft on a center axis of the flow passage.
 9. Awater supply apparatus according to claim 1 or 2, wherein clearances areformed between outer peripheries of the blades and an inner wall of theflow passage in a state that the clearances are arranged asymmetricalwith respect to an axis of the rotating shaft.
 10. A water supplyapparatus comprising: an apparatus body disposed in a water supply flowpassage; a power generating unit removably disposed in the apparatusbody, the power generating unit comprising: a holder having an axialproximal end and an axial distal end; said holder including an axiallyextending cylindrical portion and a cover, said cylindrical portionextending from said holder distal end towards said holder proximal end,and said cover extending from said holder proximal end towards saidholder distal end, said cylindrical portion including an axial opening;a rotating shaft rotatably supported at said axial distal end of saidholder cylindrical portion in essentially a radial center of saidcylindrical portion, said shaft axially extending towards said holdercover; said holder being removably mounted on a peripheral surface of anopening in the apparatus body so that: said cover is disposed exteriorto said body and said cylindrical portion is disposed within said bodyand extends perpendicularly through a water flow path; and water flow iscapable of flowing over an exterior surface of said cylindrical portionand into an interior of said cylindrical portion through said axialopening; an impeller disposed within the cylindrical portion of theholder and disposed on the rotating shaft, the impeller being rotatableby the water flow entering the interior of said cylindrical portion; amagnet disposed within the holder and connected to the impeller so as torotate with the impeller; and a coil disposed in said cover of theholder and facing the magnet; and the impeller including bladesextending in a radially outward direction and including clearances forenabling water flow past the blades.
 11. The water supply apparatus ofclaim 10, wherein to power generating unit includes intrusionsuppression means for suppressing the intrusion of foreign substancesbetween the blades and the magnet.
 12. The water supply apparatus ofclaim 11, wherein the intrusion suppression means comprises spear-headedthread-like grooves capable of generating water flow for moving theforeign substance toward the impeller blades from rotation of theimpeller on an outer periphery of the impeller.
 13. The water supplyapparatus of claim 10, wherein a guide member for guiding water towardthe impeller is disposed above the cylindrical portion.
 14. The watersupply apparatus of claim 13, wherein the guide member is a first guidemember, the apparatus further comprising a second guide member whichguides water toward the impeller is arranged at a position where thesecond guide member faces the first guide member in an opposed mannerwith the rotary shaft sandwiched therebetween.
 15. The water supplyapparatus of claim 10, wherein in the power generating unit, the magnetis disposed inside the flow passage and the coil is disposed outside theflow passage, the coil and flow passage being separated by ahermetically sealed partition.
 16. The water supply apparatus of claim10, wherein the rotating shaft of the power generating unit is disposedon a center axis of the flow passage.
 17. The water supply apparatus ofclaim 10, wherein the clearances are formed between outer peripheries ofthe blades and an inner wall of the flow passage so that the clearancesare asymmetrically arranged with respect to an axis of the rotatingshaft.